In young adults or athletes with displaced avulsion fractures of fifth metatarsal base zone I, closed reduction and percutaneous screw fixation provides anatomical stable fixation and early mobilization.

Requiring neither active components nor complex designs, we propose and experimentally demonstrate a generic framework for undistorted asymmetric elastic-wave transmission in a thin plate just using a layer of lossless metasurface. The asymmetric transmission stems from the uneven diffraction of +1 and -1 orders on opposite sides of the metasurface, respectively. Compared with previous loss-induced strategies, the present metasurface maintains a nearly total transmission for the transportation side, but a total reflection from the opposite side, exhibiting a higher contrast ratio of transmission. Moreover, we illustrate that this strong asymmetric behavior is robust to the frequency, the incident angle and the loss effect. The present work paves new avenues to compact rectification, high resolution ultrasonography, vibration and noise control in elastodynamics and acoustics.Nonreciprocal wave transmission is fundamental to various rectifying scenarios of the directional-dependent energy flux [1][2][3][4][5]. Analogous to the electromagnetic/optical field, asymmetric acoustic/elastic-wave transmission has recently been realized based on bulk artificial materials

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